下面有三篇短文，每篇短文后有几个问题，每个问题都有四个备选答案。请仔细阅读短文，并根据短文回答其后面的问题，从四个备选答案中选择一个最佳答案涂在答题卡相应的位置上。
第一篇 Economic Knowledge in One Sentence
Once upon a time, Tanstaafl was made king of all lands. His first act was to call his economic advisers and tell them to write up all the economic knowledge the society possessed. After years of work, they presented the king with a set of books: 25 volumes, each about 40-0 pages long.